I like how this series takes short bursts of story telling. Neither of the two books has resolved any major plot points. In fact, the end of each is more like the end of a particularly exciting chapter that I've read in other books. But the breaks are good places to do so. Like playing a role playing game: "Okay, you all survived the big encounter for tonight and you are making camp, let's stop here for the week."
What I like about this is that you can read each book in a short period of time, go read a few other things, then come back to this story. It prevents it from becoming a long, drawn out thing that feels more like endurance reading by the time you are finished.. You can keep your interest easily by reading a sci-fi or horror novel in between each section of this story. So, once again like role playing: it helps prevent "burnout".
And, for Larson, it does keep you buying the later books ha ha. By not making a large resolution at the end of the section I'm currently reading, he pretty much guarantees that I'll be picking up the next in the series fairly soon. Now, while that may seem bad for the reader, at $3 each on my Kindle, I really don't mind. It's like every three of these I read costs the same as a regular $9 paper back.
And, as for the plot: It is very intriguing. It has a few familiar aspects of the fantasy novel, but also introduces some new things I've not seen before, which helps in keeping the story fresh in my mind and keeps me thinking about it.
I definitely give it an A+.